You could call Jeff Mason a sandwich savant — plenty of his customers do. The owner of Pal's Take Away, a five-year-old lunch counter sequestered inside a wine bar on 24th Street in the Mission, Mason has built a loyal following for his creations, which typically incorporate heterodox ingredients (Lao sausage, soy-yuzu mayo, Popchips) procured locally and served on pedigree bread. He has a bumper crop of positive reviews on Yelp—of 143 critiques, 122 garnered four or five stars—accompanied by descriptors like "mad sandwich genius" and "badass." But he has mixed feelings about the reviews, even the good ones, and he can't contain his animosity toward Yelp. He sums up the majority of its scribes as "people whose parents never paid attention to them when they were younger."

And yet, Mason will admit, Yelp has been pretty damn beneficial to his business. "I've been very fortunate in that about 98 percent of my reviews have been really good," he says. Word of mouth is crucial for a restaurant the size of Pal's, so much so that when Mason moved locations in 2013 and Yelp refused to transfer his reviews to the new address, he was apoplectic—"It was as if I was starting a new business," he recalls, still spitting angry. Even with his renewed stockpile of positive reviews, he sometimes worries that negative ones have a chilling effect on traffic. "If two or three days go by and business sucks, I'll go, 'S—, I got a bad review on Yelp.'" The cumulative effect is one of helplessness and supplication in the face of an unstoppable colossus. "They have you," he says of the company and its users. "You're in it whether you want to be or not, and that's what's so frustrating."

Yelp and its millions of user-generated reviews turn 10 years old this month. And while Mason and many of his restaurant industry colleagues might wish for the website's sudden demise, Yelp is not going anywhere. On the contrary, it's going everywhere: It launched in Mexico in March, Japan in April, and Argentina in May. Currently available in 27 countries and 15 languages, it clocks some 132 million monthly users, 20 percent of whom read and write restaurant reviews. Miriam Warren, Yelp's vice president of new markets, sums up the company's strategy in missionary terms: "We want to bring Yelp to the world."

As Yelp has grown from a fledgling San Francisco startup with a handful of amateur reviewers to a publicly traded juggernaut bent on critiquing every corner of our earthly realm, one of its less obvious but more profound effects has been the curious emotional codependency that has developed between chefs and their legions of anonymous critics. Chefs will tell you that they hate those critics—they'll call them names, casting them as entitled, ignorant whiners desperate for attention that they can't find elsewhere (Mason's insult of choice: "complete degenerates").

But then, sometimes in the same breath, they'll admit that they need them, that their prospects for success would be dimmer without them, that Yelp is as much a savior as an antagonist. Like a horrible relationship built on great sex, the site has an addictive quality: No matter how lousy and vulnerable it makes them feel, many restaurateurs have a compulsive need to keep returning to the site, to see how they're being judged. Yelp, in effect, has become the equivalent of the toxic (or worse, abusive) girlfriend or boyfriend that they just can't quit, even as they worry about compromising their ideals and their sanity. As Charles Bililies, the owner of Souvla, a modestly hip four-month-old souvlaki joint in Hayes Valley, says, "You want some feedback, but don't want to necessarily empower people so they are controlling you." Psychologically, he says, "it's a very, very fine line to walk."

For Bililies, who spent the past five years of his life planning Souvla and typically clocks 100 hours there every week, a bad review—no matter how illogical, unfounded, or flat-out fictional (he once received an awful rating from someone who later admitted that she had never been to his restaurant)—can negate 20 glowing ones. Negative reviews hit that wounded spot, he confides, the place already made swollen and tender by repeated jabs of self-judgment and self-doubt, painfully familiar to just about anyone who has ever tried to create anything in the public eye.

"Someone will just say something, and it's like a knife all the way through," Bililies says. "One that gets me especially is when they're talking about the fact that the owner doesn't care. I've put everything I have into this, and then to read that—I'm getting emotional now just relaying this—it just crushes you." He takes a deep breath. "I'm now at a point where I try not to read Yelp anymore because it's starting to affect my overall mental state."

Another chef and restaurateur tells me that he has stopped reading his Yelp reviews entirely. "If you want to sleep at night, you just shouldn't pay attention to it," he says. Of Yelpers, he adds simply, "They can go f— themselves." (Fearing reprisals from both the company and its vocal users, the chef prefers to remain anonymous.) "If you rely on feedback," he continues, "especially if you're doing something creative, you're always going to be empty. You're only going to be as good as your last Yelp review."

The chef tells a story about a friend who owned a failing restaurant. "He made a mistake when an attractive Asian couple came in and he said, 'Hey, weren't you in last week?'" They hadn't been, and, under the assumption that the owner thought all Asians looked alike, the pair went on Yelp to air their grievances. The restaurant owner took the bait; during the ensuing back-and-forth, the chef remembers, "the woman said, 'That's the beauty of Yelp; you can get this feedback.' My friend said, 'There's nothing beautiful about Yelp.'" The chef's takeaway from this episode: "You're f— when you engage."

Unfortunately for him, modern chefs are very much expected to engage with the public, adoring and otherwise. Once widely viewed as undereducated societal rejects with knife skills, chefs are increasingly treated as local or national celebrities, their career moves covered breathlessly by food blogs, their "brands" elevated by Food Network shows, product endorsements, and international symposia where their ideas are dissected with Talmudic gravitas. And in some ways, this evolution of their public personas is intricately intertwined with that of Yelp, a place where an obsession with food is matched only by the need to pick apart the people and places serving it.

Yelp, as it happens, was born in a restaurant. In July 2004, Max Levchin, the cofounder of PayPal, was celebrating his 29th birthday at the Slanted Door with Jeremy Stoppelman and Russel Simmons, two former PayPal engineers who at the time were part of Levchin's startup technology incubator, MRL Ventures. Over lunch, Stoppelman and Simmons talked about their idea for an email service for sharing local-business recommendations with friends. A month later, with $1 million in initial funding from Levchin, Yelp made its debut. That October, it logged its first restaurant review, a four-star assessment of a Bay Area establishment called Cafe Brioche. Eight months later, the site had 12,000 reviewers based mostly in the Bay Area. Among them were the so-called Yelp Elite, a group of prolific reviewers who, in exchange for bulking up the site's content, were plied with "exclusive" parties replete with free booze and food and "Elite" badges on their account pages.

A year later, Yelp claimed 100,000 reviews. Soon, it was outgrowing well-established competitors like Citysearch, Yahoo, and Google, all of which offered their own Yellow Pages–style services. It was also quietly encroaching on the territory of the professional restaurant critic, a figure whose gustatory pronouncements had long been the default way for diners to discern an establishment's quality without actually experiencing it.

Although the history of dining out in this country goes back more or less to its founding—after kicking the British army out of New York in 1783, George Washington and his troops chose to celebrate with dinner at the Fraunces Tavern—the history of criticizing restaurants is relatively brief. What may be the first-ever New York Times restaurant review was published on January 1, 1859. With its baroque language and windy tangents, the article reads a bit like a prehistoric Yelp review, albeit a grammatically correct one. Titled "How We Dine," it was penned by an author identified only as a "strong-minded reporter" whose editor-in-chief had commanded him to "dine everywhere...in order that you may furnish an account of all these places." Of Delmonico's, which is today generally recognized as the country's first fine-dining restaurant, the reporter wrote, "We are made nervous by the sneerful smirk of the waiter if we order the wrong wine in the wrong place," but went on to praise the "brilliant" lights and "superb" cooking. Should a diner "make the ordinary mistakes of an untraveled man, and call for dishes in unusual progression," the reporter added, "the waiter will perhaps sneer almost imperceptibly, but he will go no further, if you don't try his feelings too harshly, or put your knife into your mouth." That early, uncharacteristically literary volley notwithstanding, restaurant reviewing over the course of the next century was a somewhat scattershot pursuit. As Robert Sietsema, the former Village Voice dining critic, points out in an essay about the evolution of the form, the public tended to regard published reviews as paid advertisements for the restaurants being evaluated. From 1936 through the mid-1950s, perhaps the most trusted authority was a traveling salesman named Duncan Hines—later known for his eponymous lines of cake mix and canned frosting—who published a series of guides called Adventures in Good Eating. A sort of pre-Zagat Zagat (which itself debuted in 1979), the guides began as a list that Hines and his wife distributed to friends. Reportedly, they proved so successful that Hines sold almost two million of them between 1936 and 1947; in 1948, he had better name recognition than the vice president of the United States.

The era of the modern restaurant review didn't kick off until 1957, when Craig Claiborne became the editor of the New York Times Food Fashions Family Furnishings section. Claiborne did what no one else had bothered to do before: He established ethical and procedural guidelines for food criticism, as well as a star rating system. Under his decree, restaurants were to be visited at least three times, always anonymously, with all expenses paid by the critic's publication. Consequently, restaurant owners and diners alike began to not only take Claiborne's recommendations seriously, but also accept the idea that such reviews could have a profound effect on business.

Fifty years after Claiborne first donned his reviewer's cap, restaurant criticism finally reached its journalistic apotheosis in 2007, when Jonathan Gold, then writing for LA Weekly, became the first restaurant critic to win the Pulitzer Prize—his irreverent, crazily evocative reviews covered establishments as varied as gelato carts, strip mall Chinese joints, and expense account steakhouses. But while the prize lent some establishment gloss to professional food criticism, the Internet was already undermining it with scores of food blogs whose numbers metastasized in proportion to the country's growing fixation with food and restaurants. Sites like Grub Street and Eater obsessively detailed the mechanisms of the restaurant industry, publishing so-called Plywood Reports that built anticipation of a restaurant's opening to the DEFCON levels previously reserved for Hollywood blockbusters. Being the first to issue a verdict on a new place became an increasingly competitive sport, with many bloggers happily accepting free preview meals doled out by publicists. Whereas the lag time between a restaurant's opening and its first reviews used to be months, it was now a matter of weeks.

Yelp tilted the scales even further away from the increasingly beleaguered restaurateur (and his long-time bête noire, the newspaper critic) and toward the anonymous reviewer: No longer did you need to build a WordPress or Blogger site to express your opinion—you required only an email account, a log-in name, and some idle time. The first verdicts on a new restaurant could now be Yelped on the establishment's maiden night, well before any kinks in service or food prep could be ironed out. And even more unkind to restaurants—works in progress on even their best days—was Yelp's acceptance of anonymous reviewers. Try as chefs might, there was simply no telling who was responsible for the insults.

A regular, impartial diner? A publicist? A disgruntled former employee with a bone to pick? There was, and still is, no way of discerning. As Yelp's content mushroomed—by 2012, it had logged some 25 million reviews—Stoppelman, as CEO, used some of the millions he had raised in venture capital funding to set up sales call centers in San Francisco and New York.

Then, as now, much of the site's revenue came from selling ad space to small businesses: In 2011, local ads counted for 70 percent of its $83.3 million in sales. Once a business has garnered several reviews, a sales rep will encourage the owner to "claim" his or her page; if the business complies, the rep will then offer it a $300 to $500 monthly sponsorship, which allows the owner to advertise elsewhere on the site.

For a lot of chefs, these sponsorships just add insult to injury. Not only do they get to see their livelihood vivisected every day, but they also get the questionable privilege of underwriting the carnage. Unsurprisingly, many business owners see this as a thinly veiled form of extortion, and some claim that their ratings have fallen or favorable reviews have been buried after they declined to buy advertising. In 2010, several businesses across the country filed multiple class action lawsuits that accused Yelp of extortion and fraudulent practices. In response, the company claimed that the disappearance and reappearance of positive and negative reviews was simply a function of the site's automatic filtering system. Although the largest lawsuit was dismissed in 2011 (the plaintiffs are still appealing that decision), allegations of shady sales practices continue to run rampant. Hoss Zaré, owner of the Fly Trap, claims that after he turned down several Yelp sales calls, "65 five-star reviews went away." ("Advertising and your position on the site have no correlation, none whatsoever," Yelp's Warren states crisply. "Some people make that correlation because it's tough to receive bad reviews.")

Many chefs interviewed for this story also complained of how easy it is to game the system: Anyone can review a restaurant, regardless of whether they've actually been there or of their relationship to the owner. The company does have some standards: Under its terms of service, users agree not to write fake or defamatory reviews, compensate or be compensated by someone to write or remove a review, or "threaten, stalk, harm, or harass others." After one chef-owner didn't renew a tenant's lease, a big review calling him a fascist landlord appeared on the Yelp page of one of his restaurants. "So they removed it," the chef-owner says. "But short of that, you can say terrible things—'I saw rats on the dinner plates, cockroaches coming out of people's ears.'"

And yet, the feedback inarguably has its uses, for both restaurateurs and their customers: After a few Yelpers complained about Souvla's napkins, Bililies swapped them for another brand. When they complained about the portion size of the salads, Bililies increased it. So while the chef would rather opt out of the Yelp machine, he recognizes that he can't, entirely. Like Mason, he admits that the site can drive a lot of business his way. "The other day," he says, "there were two people who came in and were like, 'You have 67 reviews on Yelp, and that's why we came.'"

The question of whether to engage with (or pander to, or grovel before, or pour abuse upon) random, anonymous Yelpers is a perplexing one for many chefs. Do you respond to the strangers attacking your life's work, the ones who don't think of you as a real person? Do you prioritize customer satisfaction over personal conviction? Do you take the "customer is always right" approach and accede to every niggling demand?

These are questions that have long nagged Teague Moriarty, perhaps to an even greater degree than many of his peers. Moriarty, who owns three restaurants with his fellow chef and business partner, Matt McNamara, has repeatedly responded on Yelp to poor reviews. Moriarty's earnest mea culpas to the pissed-off and self-righteous are painful to read. To Amber M., who complained of a "strange" server, "forgettable" risotto, and "dry" guinea hen, Moriarty replied that he had "worked extensively...on many of the issues you've raised" and that "we hope you will give us a chance to change your mind. If so, please let us know when you're coming in!"

"I want other people to see that we respond," the chef says. "But I want to get those people back into the restaurant." If trying to placate unhappy strangers can register an emotional toll, Moriarty prefers not to dwell on it. "At a certain point you've got to be the bigger person," he says. "For me, it's dangerous to get into the mindset of 'Oh, they don't know what they're talking about.' Even if they're not knowledgeable, they're still paying customers. It just matters that they have a good time. For us, we have to fix it with Yelp."

That's what Moriarty and McNamara did at their newest restaurant, the Square in North Beach, after they rolled out an automatic 15 percent service charge, a feature that they employ without controversy at their first and more upscale restaurant, Nob Hill's Sons & Daughters. At the Square, Moriarty says, "people f— hated it. I think we were taken aback by the hatred." So they abolished the charge. "Once you get past the emotional aspect" of Yelp, Moriarty reflects, "it's a wonderful thing. Never before have I had this overview of my business. I think that is really valuable."

Listening to Moriarty is not unlike listening to an artist or writer who has just had his work drawn and quartered by a paid critic: It's a painful, humbling, and potentially humiliating experience, yet also a potentially useful one. But Moriarty is the exception within the cloistered world of San Francisco chefs—most chafe at receiving advice and insults from people whom they perceive as knowing little about the restaurant business, especially when those people's reviews, no matter how boneheaded, can have real-life consequences: A 2011 Harvard Business School study found that a one-star increase in a restaurant's Yelp rating led to a 5 to 9 percent increase in revenues.

It's this last fact that has led Ryan Cole, the general manager of Stones Throw, a nine-month-old Russian Hill restaurant, to set aside his animus toward Yelp and focus instead on its utility. He and his staff look at reviews "multiple times a day" for feedback on everything from servers to decor. Although Cole doesn't engage with reviewers, he regards them as invaluable in helping Stones Throw establish its "brand perception." Given the dizzying number of restaurants that open in the city each month, Yelpers, he feels, are crucial in getting the word out, particularly about smaller restaurants like his. "If Yelp were to go away," he says, "for a business like mine it would be detrimental."

It's not only chefs and restaurant owners, of course, who have a psychologically fraught relationship with Yelp—the same could be said of any small-business owner. When you're struggling to stay above water, facing an anonymous, frequently contentious army of critics can suck you under—as happened a few years ago when a local bookstore owner named Diane Goodman replied to a customer's bad review with some nasty emails that the customer then posted—where else?—on Yelp. When Goodman tracked down the customer's address and went to his house to apologize, a physical altercation ensued and Goodman was booked on battery charges. "I've never met any store owner who likes Yelp," she later told a reporter. "It's evil."

But selling food, unlike selling books, is not a purely transactional endeavor. It can be an intensely personal experience for both the chef and the diner, one that is all but inseparable from the deeply human impulse to nurture and be nurtured. To feed people and then have them kick you in the face for your troubles—it feels wrong. There is no Yelp for painters or dancers or filmmakers (though authors have to contend with customer reviews on Amazon and Goodreads), and plenty of chefs will tell you that what they're doing is no different. Pretentious as it may sound, food is their art, their life story. When it's misunderstood or slammed, so, by extension, are they: If you prick them on that user-generated-business-review site, do they not bleed?

It's easy to forget that not that long ago, small restaurants made a name for themselves without the help or hindrance of Yelp, buoyed only by word of mouth or, less frequently, by a savvy publicist. "How did we communicate [in the old days]?" Staffan Terje, the chef-owner of Perbacco, wonders aloud. "You'd pick up the phone. We've learned so many different ways of communicating that I think we forgot how to interact."

It's not that Yelp invented consumer criticism—for all of the minute details that Yelpers like to nitpick, says Terje, "there are no new things to complain about or compliment on." The difference, of course, is that today criticism is often free of personal interaction: Instead of flagging down a waiter to complain about lukewarm salmon, you can wage an all-out Internet attack, free of the restraint that usually moderates face-to-face confrontation. And the enthusiasm with which people rush to review restaurants illustrates how much of a spectator sport dining out has become, a trend manifested both literally, as in shows like Top Chef, and in the sheer number of restaurants vying for customers. Who wants to become a regular when there are so many new places to try? Yelp is less the problem than a symptom of a paradigm shift within food culture, "where everything is about the best new restaurant or rising star chef," says Richie Nakano, the chef-owner of Hapa Ramen. "We should be giving lifetime achievement awards, like, your restaurant made it 10 years—way to go!" Instead, we give all the attention to the latest arrivals and splashiest debuts (this magazine being no less guilty of that crime).

And thus we arrive at the imbalance central to any toxic relationship: Chefs need customers, but customers don't need chefs. Which is not to say that all Yelpers get off on flaunting their (perceived) power. Phil Hamilton, a video editor who has written over 1,000 reviews since joining Yelp in 2005 and has been a member of the Yelp Elite for nine years running, acknowledges that the term "Yelper" has "such a negative stigma to it." Initially, he was excited to be part of a community and used his reviews, most of which are positive, as a kind of postcollegiate creative outlet. But the "current crop" of reviewers, he feels, "has made such a bad name for everyone," and the strong tide of negativity has pushed away more even-keeled reviewers like him. "I wish that people wouldn't paint everyone with the same brush," Hamilton says. "We're not all 23-year-olds who want to eat for free and get hammered and put emojis in our reviews."

The company, unsurprisingly, takes a rosier view of the way its community has evolved. "Gosh, I would hope that it changes," Yelp executive Warren chirps. "For something to gain really big traction, it has to get bigger and appeal to more people." Far from creating an impersonal gulf between reviewer and restaurant owner, Yelp, she claims, "is increasing this human factor" by encouraging interaction between the two. And where the customer is concerned, she continues, "we think about [Yelp] as a tool to minimize risk."

But the question remains, are restaurants really a risk that needs minimizing? After all, it's not a mortgage—it's lunch. To believe otherwise speaks to an increasing desire on the part of consumers to have our experiences tailored to our specifications, free of surprise, bereft of serendipity. And in its drive to give everyone a say, Yelp may be rendering individuals' voices meaningless, just more white noise to block out. "I can't remember the last time I read a review," Hamilton says. "There are so many nowadays that it's impossible to weed through the muck. Now I use it more for business hours and directions."

For their part, few chefs would argue that Yelp has absolutely no utility—if nothing else, it does make a good phone book. Like anything found on the Internet, it is what you make of it, be it a research tool, a time suck, or a key for unlocking personal demons. While it doesn't make restaurants discernibly better or worse, it does make our expectations of them greater than they have ever been, or perhaps should be. Maybe, chefs say, diners need to ask themselves why they've become as emotionally dependent on restaurants as chefs themselves have become on Yelp. When did restaurants become crucibles for people's hopes and disappointments? "In the old days," laments Dennis Leary, the owner of six bars and restaurants in San Francisco, "customers were here to make their own fun. It's a night out, and that's all it really should be." After all, he says, "we're not saving lives."